Johnson's dad, Cheltenham boss Gary, has labelled his son "an information sponge" and ahead of kickoff he the City chief spent 20 minutes with Mourinho, getting managerial advice and picking the brain of the United boss.

It was a gesture hugely appreciated by Johnson, who had also spent the days ahead of the match further delving into the mind of Mourinho, reading books on - and by - the Portuguese.

Johnson had also spent time at home, using the match analysis tool that he has in his living room, looking at United's recent performances, Mourinho's tactics and use of substitutions, as he left no stone unturned in his quest to shock United.

As such, his side were ready for what United threw at them, despite Mourinho making 10 personnel changes to the side that had beaten West Brom last weekend.

(Image: PA)

The pair spent 20 minutes chatting (Image: PA)

Johnson certainly did his homework (Image: REUTERS)

Johnson had also gone so far as to spend £450 on a bottle of wine as a gift for Mourinho - flying in the 2004 Barca Velha Red especially from Portugal - but in the end, City's goalkeeper coach made sure it didn't go to waste.

"The wine is breathing at the moment," revealed Johnson post-game. "To be honest, they shot off. I had a go at my goalie coach, I saw him having a glass.

That's bad news for ex-City boss Gary, who was hoping his son would be passing it on to him for Christmas.

He told BBC Breakfast: “I can see myself getting a very expensive bottle of wine for Christmas from Lee."